These days smartphones let you do practically anything, but you still have to reach in to your pocket to use them. Now, researchers at Nokia aim to solve that problem with a magnetic ring dubbed Nenya, after a ring found in The Lord of the Rings, that you can twist around your finger to control your phone.

The ring itself looks like a standard piece of jewellery, but is actually a strong magnet. Moving the ring causes changes in the surround magnetic field, which are picked up by a bracelet worn by the user that connects to their phone via Bluetooth. You rotate the ring to pick from a number of options, which could be memorised, played as audio through headphones, or displayed on a screen, then push the ring towards your fingertip to select. The options could include asking a caller to hold, or updating your location on a social network.

Users can turn the ring with either their other hand or the same hand, though the latter is more difficult. The researchers conducted two small trials and found that people could accurately position the ring in roughly 45 degree increments, suggesting that a ring-controlled menu could contain up to eight options. They will present their findings at the Conference on Human Factors in Computing Systems in Vancouver, Canada next month.

There are few problems to solve before you can start ringing your phone, however. The bracelet is currently a rather bulky and unattractive device, but the electronics inside could be incorporated into a watch or jewellery bracelet, and the system also detects the ring when users move about, which could execute unwanted commands. There's also the issue of walking around with a great big magnet on your finger, with the potential to attract nearby metallic objects and damage credit cards or hard drives.

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